Rocking railway journal box



Sept- 11, 1956 P. G. PALMGREN RocxING RAILWAY JOURNAL Box- 7Sheets-Sheet 1 Filed June 2l, 1950 Sept. l1, 1956 P. G. PALMGREN ROCKINGRAILWAY JOURNAL BOX 7 Sheets-Sheet 2 Filed June 2l, 1950 Sept. 11, 1956P. G. PALMGREN ROCKING RAILWAY JOURNAL Box 7 Sheets-Sheet 3 Filed June21, 1950 Jaffe/57" Sept. 11, 1956 P. G. |=-ALMGREN RocKING RAILWAYJOURNAL Box Filed June 2l, 1950 7 Sheets-Sheet 4 sept. 11, 1956 P. G.PALMGREN 2,762,317

RocxING RAILWAY JOURNAL Box Filed June 21, 1950 7 Sheets-Sheet 5Sepfgll, 1956 P. G. PALMGREN 2,762,317

ROCKING RAILWAY JOURNAL BOX Filed June 2l 1950 '7 Sheets-Shogi, 6

Sept 11, 1956 P. G. PALMGREN 2,762,317

ROCKING RAILWAY JOURNAL BOX Filed June 2l, 1950 7 Sheets-Sheet 7 UnitedStates Patent RoCKrNG RAILWAY JOURNAL Box Per Gunnar Palmgren,Philadelphia, Pa., assign'or to SKF Industries, Inc., Philadelphia, Pa.,a corporation oi Delaware Application June 21, 1950, Serial No. 169,357

6 Claims'. (Cl. 10S-223) This invention relates to a journal box forrailway axles arranged to permit limited axial motionof the axle withina self-aligning bearing assembly.

A principal object is to provide a journal'box capable of swinginglaterally to accommodate the unavoidabl weaving motion of the axle onthe track.

Another object is to construct 'the journal box so that it may followthe weaving motion of the axle by rocking laterally on an outer curvedsupportingsurface. -Y

Another object is to limit the lateral rocking of the box substantiallyto the extent'of the relative lateral motion between frame and axle.

Another object is to construct the rocking surface so that it creates aforce tending to reverse its direction of swing, said force startingfrom zero and increasing in value as the box tilts farther from uprightposition.

Still another object is to construct the rocking surface so that therocking movement is controlled either by steps or smooth rolling motionagainst increasingl resistance.

A further object is to contour the interseating surfaces of the box andframe so that the carV load will `produce couples tending to slow downswinging of the axle relatively to the frame. i

In a preferred embodiment, the invention contemplates a railway axlejournal box and side frame assembly wherein the axle is afforded therequired limited axial oat through freedom of the box to rock intheframe, the resulting angular displacement of .the box with respect tothe axle journal being accommodated through medium of a singleself-aligning roller bearing for said journal suitably mounted in thebox.

Fig. l shows in sectional elevation the railway journal box of thisinvention;

Fig. la is a sectional elevational view showing thebox and bearing outerrace tilted by movement ofthe axle totheleft;

Fig. 2 is a view similar to Fig. 1 showing another and preferredembodiment of the invention;

Fig. 2a is a view similar to Fig.. la illustrating the mode of operationof the embodiment shown in Fig. 2;

Fig. 3 shows a front elevational view ofthe boxassembled in the sideframe of a railway car;Y

Fig. 4 is an end view of theframe and. boxfassembly as viewed from theline 4-4,.Fig..3; y

Figs. 5, 6, 7 and 8 are fragmentary sectional elevational viewsillustrating modifications within the sc'ope of :the invention, and f' yFigs. 9 and 10 are diagrammatic views illustrating `two differentapplications of the principles of the invention.

Because of the necessity for axial clearance between wheel ange andrail, and because of Vthe conical Vshape of the wheel rim, there isalways a tendency in rail cars for the axle to move back and forthaxially whenthe car is in motion. In addition, the rail is never quitestraight which also results in axial motion of theaxl. In order toreduce communication of axle motion tov the truck, andvv thence to thecar body, journal `bearings of the-plain type are allowed clearance-foraxiall oatfbetweenthrust surfaces of journal and of the brass of thebearings. This permits the journals to slide axially across the brasspil-L lows to the limit of the total clearance before'striking thethrust shoulders. 'f

The present invention provides a journal box organization, including aself-aligning anti-friction bearing as'- sembly, wherein the box isaiforded freedom for angulardisplacement of suicient magnitude toaccommodate the axial weaving of the axles without communication ofundue amounts of that axial motion to the trucks of the' car body. Inthis organization the self-aligning bearing assembly functions to permitthe relative angular move-` ments between the box and the axle whichmust neces-z sarily accompany the aforesaid angular displacements of thebox. "Q

In one embodiment, the invention consists of a journal box 1 providedwith a truck frame lsupporting surfacelil` at the top in the form of asegment of a cylinder struck from a horizontal axis through the center 3of the bea'ry ing, normal to the axis of the journal, ther said surfacelbeing curved therefore in the direction longitudinally "of the axle. Thebox is also provided with 'lugs 5d and 5b integral with the box andarranged to limit its angular moi` tion, and to support lateral loads,as its cylindrical vsu face rocks on a at surface 6 in the side frame 7.The boil contains a single self-aligning roller bearing 8 for theaxlejournal having an outer raceway surfacem9 of spheric-lf form alsocentering at 3. The box has a widthconsidf ably greater than that of theside frame 7, -and the sid lugs at the sides have a horizontal spreadgreater than tli pedestal opening, as in Fig. 4 wherein the box isshown" in the pedestal opening. v Lugs 5a and 5b are spacedfroinl thewalls of the side frame by'clearances `10er and 10b which correspondwith the amount of rocking resulting Y when the axle moves axially fromcentral to extremele'ft'fi or right, position with respect to the Asideframe. Y When tHe"4 axle moves to the left, the inner face of lug 5astrikes thej adjacent wall 11a of the side frame, while lug 5b strikjes"wall 11b when the axle moves right. Fig. `1 showsuthe box in centralvertical positon. It will be noted thatin Fig. 1a the center 3 of theinner racel ofV the bearingjhas moved with axle 12 horizontally to theleft, asindicated by arrow A. The box and outer race have rocked throughsmall angle d. r

Fig. 1 shows the self-aligning roller bearing, fat the left] end of theaxle, in its upright central'position. The lugs 19a and 1911 at the topof the box, spaced Ifrom the side walls of the frame by small clearances20a and v20Mb serve!l to position the box close to the center whileallowing'the necessary swing. Since the axle would seldom lie perfectlyperpendicular to the direction Aof the track, it will-y axle to point3a. It also carries,y the inner race 13 andy rollers 14 the samedistance.y lressure of the load oriv tlie cylindrical top of the box.prevents the latterffromiovl" ing horizontally left but forces it torock as' illustrated.`

Freedom for this rocking v mc` ve`ment,with its resultant angulardisplacement of the box with respect tothe axle,-v`v is afforded by theself-aligning bearing which provid's the necessary horizontal axis ofoscillation for 'the axle@ journal in the box, said axis intersectingthe bearingmcer'v ter 3 normal to the journal axis and paralleling'orap?" proximately paralleling the aforesaid axis of thel rocking surface2. Since axial motionof theaxle occurs only; when the train travels, therollers will -fllow a helical path over the 'outer raceway up' 'tdtheamount of tari-"5'" gential pressure across-.the `contact surfacef9 atwhich*v ,lttllmbodmeat @which ,theaxs ofthe Cylindrical rocking surfacecoincides with the center 3 of the spherical outer raceway of thebearing, the outer ring of the bearing and the box will `rock shownlinFig.v la,'movingthc location of load s upport'to the leftfromyerticalplane 16, which contains' ltl'1e centers ofbearingUand ofbox when in their upright positions, to plane 17 which containsthecenter ofthe bearing -in its shifted position. In this case the boxlrocks without raising the frame .relatively to the horizontalcenterlineof the axle, encountering only the extremely low resistance ofrolling friction, and limited by the striking of thelug 5a against wall1in of the frame.` Since the line of loading always Ipassesverticallyvthroughthe center 3 of the supporting bea-ring, the, boxremains stable .in every rocked position. Forces created by thecontinual weaving motion among car bodies, frames, trucks and axles, dueto conicity of wheel rims, unevenness of tracks, and play betweenmembers of truck frames, ac-t to keep the box in oscillation withinlimits permitted by the lugs.

If the cylindrical truck frame supporting surface is struck from an axiswhich lies below the bearing center 3, say through the point '4 in Figs.2 and 2a, so that the surface has a radius longer than the distance frombearing center to the said surface, rocking of thebox as illustrated inFig. 2a, will move the said axis of the cylindrical surface to 4a,whichis a greater distance than it moves the bearing center. The planeof load application lby the frame to the top of the box will thus havemoved from location 16 to location 1S wherein the said plane passesthrough the shifted point 4a. The plane of load application, therefor,stands a distance g to the left of the support plane 17, so that acouple is created 'tending to reversethe direction of swing of the box,the couple having l a value Ain pounds inches equal to the product ofload ture increases as the surface progresses on either side of theplane of symmetry, as illustrated at 2l in Fig. 5, will throw theloading plane further and further beyond the supporting plane, as thebox rocks further and further from the vertical position. In otherwords, the restoring force will increase at a higher rate thanwith acylindrical surface. When the radius of curvature reaches infinity thesurface becomes flat and the loading plane shifts instantly from thecenter of the at to its edge. A flat surface, therefor, maintains thebox in a definite position until the rocking couple overcomes therestoring couple, i. e., until force along the center line of theaxletimes its distance from the flat, overbalances the load timesonehalf the width of the dat.

Obviously also the tilting characteristic of the box may come in partfrom an antifriction bearing of the type having its inner instead of itsouter race of spherical form, as shown in Fig. 6, wherein the inner racering is indicated by the reference numeral 22 and the spherical racesurface ofthis ring, the center of which correspondsto the center 23 ofthe bearing, by the reference numeral 24. The rollers 25, in thisinstance, have concave rolling surfaces conforming to the convexsurfaces 24 of the inner race and 26, 26 of the outerrace. The requiredtilting characteristics may be obtained also by the use of abearingassembly which includes an adapter for the bearing', see Fig. 7,having a sphericalsnrface 27 for contact with a matching sphericalsurface 28 within the box, the bearing 29 in this case beingofconventional double row tape-red type. Any such spherical surfacecombined with a rocking surface in accordance with the principles setforth above will permit lateral motions of the axle and provide the samerestoring forces at every location of the loading plane as lin the abovedescribed embodiment, the value of those forces depending upon the ratioin that loading plane, of the radius of curvature of the rocking surfaceto the distance from the bearing center to the rocking surface.

The supporting surface may possess different forms at diterentsymmetrical locations on either side of the central plane of the box,which give it an action characteristic. of each location. A supportingsurface composed of a series of ats each successively diverging towardthe axle at a small angle from the preceding one, would regulate thetilting in steps, as distinguished from the smoother action provided bycurves. A polygonal surface of this character is illustrated in Fig. 8wherein as in the otheriigures theside frame is indicated by thereference numeral 7, and the individual flats of the rocking surface ofthe journal box by the reference numeral 30. yThe angle between theadjoining flats should not exceed that which would result in the boxmoving into an unstable position when shifting from one flat to another,i. e the center of the bearing should never advance l frame, and Figures2, 5 and 7 illustrate organizations in which 'restoring couples rcomeinto play as soon as the box `starts tilting from vertical position, andincrease with continued tilting. The principle of the inventori,however, as indicated above, may tind other embodiments.-

In one lmodification, Fig. 9, the frame surface 41, or if desired asupplementary surface attached thereto, is

` concave in form so as to embrace the convex seating surface 42 on thebox. With this arrangement, and for any given angular displacement ofthe box, the axial displacement of the interseating lor contact areabetween the surfaces will be not only greater than the axialdisplacement of the bearing center, but the ratio will be relativelyhigh. Thus, a displacement of the bearing center 3, Fig. 9, from thevertical .plane 43 tothe point 3a,'will be accompanied by an axialmovement of the contact area from the plane 43 to the vertical plane 44.This affords a relatively quick and large restoring couple which may beindicated by the arrows 45 and 46.

In another modification, Fig. l0, the frame may present a convex seatingsurface 47 to a convex box surface 48. With this arrangement the contactarea betweenv the surfaces will have a lesser axial displacement thantheaccompanying displacement of the axle. Thus, a movement of thebearing center 3 from the vertical plane 49 to the vertical plane 52,will be accompanied by an axial movement of the contact area from theplane 49 to the plane 50. In this case, therefore, the restoring coupleis absent, and a small upsetting couple, indicated by the arrows 53 and54, is developed. v

In general, the balanced condition illustrated in Fig. 1, or therestoring couples described above, are considered desirable, since theyeither avoid unstabilizing forces or actually produce lforces tending tostabilize the axle in central position and the box in upright position.The embodiment of Fig. 10, which in effect tends to stabilize the axlein the positions of extreme axial displacement from the central positionwith the box tilted to one or other side of the upright, may be founduseful under certain conditions of load and structure. It is evident,also, that the required rocking action may be obtained by provision of atiat frame-supporting surface on the box and a coactin'g convex seatingsurface on the frame.

Such arrangement, however, while falling within the broad principle ofthe invention, tends to increase the magnitude of the hp-setting couple.

A11 the above discussion of supporting surfaces assumes their formationaccurately to specification. Such accuracy may prove impractical in somecases especially when using cast iron parts. Wear or pounding may alsoalter original surfaces and thus change the rocking action originallydesigned. This invention extends to all such variations.

As described above, the invention contemplates a journal box having aframe-supporting surface offset from the center line of the axle andarranged for coaction with a suitably formed frame surface to permitlimited rocking movements of the box in the frame, together withselfaligning means within the box affording freedom for the accompanyingrelative angular movements between the box and the axle. The forms ofthe interseating surfaces, their location, and the form and arrangementof the selfaligning means may vary widely without departure from theinvention.

It will be understood that the term rolling as used in the appendedclaims is intended to embrace tilting and any other form of relativemovement between the interseating surfaces of the frame and journal boxwhich is substantially free from sliding friction.

I claim:

l. A journal box for the axles of rail cars, said box comprising aself-aligning bearing assembly for the axle journal affording freedomfor relative oscillatory movement between the axle and the box about ahorizontal axis intersecting the center of said bearing assembly andnormal to the journal axis, said box having also a surface remote fromand above said axis of oscillation convexly curved in the directionlongitudinally of said axle and forming a seat for the side frame of arail car truck on which the box may rock with respect to said frame inresponse to longitudinal displacement of the axle, said seating surfaceand bearing jointly affording freedom for said longitudinaldisplacements of the axle with respect to the frame, and the radius ofthe said curvature of the seating surface exceeding the distance of saidsurface radially from the said axis of oscillation.

2. A journal box according to claim 1 wherein the curved frame-seatingsurface defines an arc of a cylinder.

3. A journal box according to claim l wherein the radius of curvature ofthe frame-seating surface is Variable and increases progressively oneach side of a median position. l

4. A journal box according to claim 1 wherein the curved frame-seatingsurface exhibits a polygonal profile in the vertical cross sectionsnormal to said horizontal axis.

5. A journal box according to claim 1 wherein the convexly curved seatfor the side frame supports'a concave surface on the underside of saidframe, the radius of the said seat being shorter than the radius of saidconcave surface.

6. In a rail car side frame and axle journal assembly, a journal boxcontaining a self-aligning bearing for the journal comprising an innerrace ring secured against axial displacement to the journal, an outerrace ring secured against axial displacement in the box, and rollingelements confined between and securing said rings against relative axialdisplacement, said bearing affording freedom for oscillation of the boxrelative to the axle about a horizontal axis through the bearing centerand normal to the journal axis, a side frame-seating surface on the boxabove said bearing center on which said frame is supported in verticalalignment with said center, said seat being convexly curved in thedirection longitudinally of the axle so as to allow the box to rock onthe frame in response to axial displacements of the axle withv respectto the latter, and the radius of curvature of said seating surfaceexceeding the distance of the surface radially from said horizontalaxis.

References Cited in the le of this patent UNITED STATES PATENTS1,813,975 Von Zweigbergk July 14, 1931 1,943,055 Brittain Ian. 9, 19341,966,923 Couch `luly 17, 1934 2,031,777 Johnson Feb. 25, 1936 2,071,947Oelkers et al. Feb. 23, 1937 2,405,132 Brittain Aug. 6, 1946 2,488,853Cottrell Nov. 22, 1949 FOREIGN PATENTS 350,298 England June l1, 1931377,395 England .Tuly 28, 1932

